Influence of the preliminary annealing conditions on step motion at the homoepitaxy on the Si(100) surface

In this paper, the motion of steps SA and SB on the Si(100) surface in the process of Si Molecular beam epitaxy (MBE) is explored. The study was carried out by means of the reflection intensity dependence behavior analysis of reflection high-energy electron diffraction (RHEED) corresponding to the (2×1) and (1×2) reconstructions. Superstructural rearrangement from a two-domain to a single-domain surface is associated with the bilayer step formation, which occurs due to the different motion rates of the steps SA and SB. Based on the research conducted, the conditions under which the step doubling occurs were determined. A behavior analysis of the diffraction reflection intensity dependences showed that an increasing of preliminary annealing time and temperature facilitates to the faster convergence of the steps SA and SB, but to the slower recovery of the initial surface. The presented experimental results indicate that step movement rate difference depends on the step A edge kink density

Показатели развития городских образовательных институтов как факторов экономического и пространственного развития города и городской агломерации, с опорой на результаты международных исследований, посвященных данной проблематике

In the current economic situation, both in the Russian Federation and in the developed countries of the world, the education system is increasingly becoming a factor in successful economic and spatial development

Parietal and occipital hair loss patterns in initial stages of androgenic alopecia in men

Background. The initial stages of androgenetic alopecia in men are characterized by a variety of clinical manifestation in the parietal or occipital scalp regions. However, the differences in the pathogenesis of hair loss patterns are not well understood, selective treatment has not been developed. Aims. Trichological characteristics of patients with initial stages of androgenetic alopecia with identification of genetic and non-genetic factors that determine the hair loss in the different scalp regions, and their response to conservative therapy. Materials and methods: Trichograms were photodocumented using an AramoSG microcamera (Republic of Korea). The genetic factor was analyzed by mini-sequencing of single nucleotide polymorphisms rs929626, rs5919324, rs1998076, rs12565727, rs756853. The non-genetic factors study included hormonal status (total and free testosterone, dihydrotestosterone, 17OH-progesterone, dehydroepiandrostenone, SHBG) and blood content of trace elements (Mg, Ca, Zn, Cu, Se, Fe) and vitamins (B12, D, E, folic acid). Conservative treatment was topical application of a minoxidil 5% (twice-a-day, 4 months) and a micronutrient deficiencies personalized correction. Results. The study included 47 man with initial stages of androgenetic alopecia. Their trichological examination showed two patterns, consisting a predominant decrease in the hair density and diameter in the parietal and occipital scalp regions, which were subgroups formation criteria. An intergroup comparison revealed similar genetic risk, while hormonal parameters (increased dihydrotestosterone levels, a decrease in free testosterone) characterized the subgroup with parietal hair loss pattern. Also, a multiple deficiency of Zn, Cu, Se and vitamins B12, D, folic acid was detected in all patients. Subsequent conservative treatment had a positive effect in patients with parietal hair loss pattern, while in patients with occipital pattern no significant response was observed. Conclusions. The study develops ideas about differences between androgen-dependent parietal and androgen-independent occipital hair loss patterns in the initial stages of androgenetic alopecia, which requires different approaches to their conservative therapy

Electron and hole injection barriers between silicon substrate and RF magnetron sputtered In2O3 : Er films

In2O3 : Er films have been synthesized on silicon substrates by RF magnetron sputter deposition. The currents through the synthesized metal/oxide/semiconductor (MOS) structures (Si/In2O3 : Er/In-contact) have been measured for n and p type conductivity silicon substrates and described within the model of majority carrier thermoemission through the barrier, with bias voltage correction to the silicon potential drop. The electron and hole injection barriers between the silicon substrate and the film have been found to be 0.14 and 0.3 eV, respectively, by measuring the temperature dependence of the forward current at a low sub-barrier bias. The resulting low hole injection barrier is accounted for by the presence of defect state density spreading from the valence band edge into the In2O3 : Er band gap to form a hole conduction channel. The presence of defect state density in the In2O3 : Er band gap is confirmed by photoluminescence data in the respective energy range 1.55–3.0 eV. The band structure of the Si/In2O3 : Er heterojunction has been analyzed. The energy gap between the In2O3 : Er conduction band electrons and the band gap conduction channel holes has been estimated to be 1.56 eV

ИНТИМАЛЬНАЯ САРКОМА ЛЕГОЧНОЙ АРТЕРИИ, ПРОТЕКАЮЩАЯ ПОД МАСКОЙ ТРОМБОЭМБОЛИИ ЛЕГОЧНОЙ АРТЕРИИ: РЕЗУЛЬТАТЫ ХИРУРГИЧЕСКОГО ЛЕЧЕНИЯ

HighlightsThe article describes a rare case of surgical treatment of pulmonary artery intimal sarcoma. The authors analyzed the causes for incorrect diagnosis of pulmonary embolism in detail, and proposed alternative options for distinguishing the diseases under consideration. Moreover, the authors analyzed different surgical treatment modalities of intracardial sarcomas, and demonstrated the prospect of using molecular hydrogen as a component of an anesthetics during surgical interventions with cardiopulmonary bypass. AbstractThe article describes a rare clinical case of a patient with pulmonary artery sarcoma. The absence of specific symptoms of sarcoma, as well as features of developing cardiovascular and respiratory failure, characteristic of pulmonary embolism, contributed to the incorrect diagnosis. The article analyzes the main problems of primary diagnostics, and proposes new parameters for evaluating manifesting symptoms and the results of additional examination, which should improve the results of surgical treatment of malignant tumors.Основные положенияВ статье представлен редкий случай хирургического лечения интимальной саркомы легочной артерии. Детально проанализированы причины гипердиагностики тромбоэмболии легочной артерии, а также предложены альтернативные варианты дифференциальной верификации рассматриваемых заболеваний. Рассмотрены возможные варианты хирургического лечения сарком внутрикардиальной локализации. Кроме этого, продемонстрирована перспектива применения молекулярного водорода в качестве компонента анестезиологического пособия при выполнении оперативных вмешательств в условиях искусственного кровообращения. РезюмеВ статье описано редкое клиническое наблюдение пациентки с саркомой легочной артерии. Отсутствие специфических симптомов саркомы, а также особенности развивающейся сердечно-сосудистой и дыхательной недостаточности, характерные для тромбоэмболии легочной артерии, способствовали постановке неправильного диагноза. В работе проанализированы основные проблемы первичной диагностики, а также предложены параметры оценки манифестирующих симптомокомплексов и результатов объективных методов обследования, что в свете повышенной онкологической настороженности позволит улучшить результаты хирургического лечения злокачественных заболеваний сердца

Indicators of the Development of Urban Educational Institutions As Factors of the Economic and Spatial Development of the City and Urban Agglomeration, Based on the Results of International Studies Devoted to This Issue

In the current economic situation, both in the Russian Federation and in the developed countries of the world, the education system is increasingly becoming a factor in successful economic and spatial development

Effect of Low Temperature on Content of Primary Metabolites in Two Wheat Genotypes Differing in Cold Tolerance

The study of cold-tolerance mechanisms of wheat as a leading cereal crop is very relevant to science. Primary metabolites play an important role in the formation of increased cold tolerance. The aim of this research is to define changes in the content of primary metabolites (soluble proteins and sugars), growth, and photosynthetic apparatus of freezing-tolerant and cold-sustainable wheat (Triticum aestivum L.) genotypes under optimal conditions and after prolonged (7 days) exposure to low temperature (4 °C). In order to gain a deeper comprehension of the mechanisms behind wheat genotypes’ adaptation to cold, we determined the expression levels of photosynthetic genes (RbcS, RbcL) and genes encoding cold-regulated proteins (Wcor726, CBF14). The results indicated different cold-adaptation strategies of freezing-tolerant and cold-sustainable wheat genotypes, with soluble proteins and sugars playing a significant role in this process. In plants of freezing-tolerant genotypes, the strategy of adaptation to low temperature was aimed at increasing the content of soluble proteins and modification of carbohydrate metabolism. The accumulation of sugars was not observed in wheat of cold-sustainable genotypes during chilling, but a high content of soluble proteins was maintained both under optimal conditions and after cold exposure. The adaptation strategies of wheat genotypes differing in cold tolerance were related to the expression of photosynthetic genes and genes encoding cold-regulated proteins. The data improve our knowledge of physiological and biochemical mechanisms of wheat cold adaptation